THE ONE chord that will energize better than ANYthing else they did? Yes, Pepper's is nice, Taxman's a good song (both don't have an appreciable opening). Really the only one besides AHDN is the afore-mentioned '1...2...3...FAW!" Yet even that can't compare (to my weatherd, feeble mind) to that G7/11/whatever chord!

Easily I SAW HER STANDING THERE. The intense count-in is really great*.

*Interesting tidbit: If you listen to the outtakes for this song, after counting the song in so often, Paul keeps screwing up and at one point gets so frustrated that by one take he yells the "1 - 2 - 3- FAWWW!!!!" that was used on the released version and has since become legendary.